You can't officially send emojis in any application unless it's built on the application itself. Facebook (Chat), WhatsApp, WeChat, and Snap10 all offer emojis in the application.

But if you want to do it everywhere, there's a long process to be able to send emojis.
It's a way I discovered months ago.

Here's a step-by-step process.
1. Copy whatever emoji you want. Find it or have someone send an emoji to you, then copy it.
2. Settings --> Language and Input --> Prediction and Correction --> Word Substitution
3. Hit the plus button to create a new shortcut. For example, you've copied a smiling emoji. On the upper field, say you put "" or anything easy to remember, and on the bottom one, paste the emoji.
4. Now on any place you can type, you can just type in "" and then the emoji should replace the text when you press the space bar.

It's long and complicated at first, but once you get used to it, you'll be able to have all the emojis you want.